Yes I have the same problem, its wierd, when I had backtrack 2 installed i could use startx in another user to see the gui.
With BT3 final and BT3 usb final I get the same error as you, i tried a few things like changing the permissions for that file but I never got it too work, Most of the programs i use on BT seem to need root provalages anyway, i know you can use suid and sudo though
Ps if you do find a soloution, please could you post it
Calypso



